Today, the use of DVR (Digital Video Recorder) or PVR (Personal Video Recorder) gives the possibility to watch movies that were broadcast or downloaded at a previous time. One important motivation for using such a recorder even for watching live television programs is the ability to pause and freeze the current program and continue to watch it later without missing the period where the user was not present.
One collateral effect of this main feature is the possibility to skip the advertisement spread in the movies. One can find in the market DVR devices that detect the advertisement periods and automatically jump forward to the subsequent movie segment. Since advertisement is an important means to finance the movie distribution, the spread of technical means to skip the adverts can lead to financial loss for the content provider.
In the document US200104982, it is described a method for encouraging the viewer to keep on watching the advertisements by carefully authoring the first or last number of seconds of a commercial break to provide a “teaser” to entice the viewer to watch multiple commercials during the commercial break, instead of skipping it using the fast forward or jump functions of the DVR. To this end, when the viewer selects a recorded program from the DVR's storage device for playback, an advertisement is first retrieved from the storage device and displayed before the main program.
However, the user is still free to skip the advertisement using the fast forward or the jump function of the DVR.
In payTV applications where content is subject to conditional access enforcement by a security module, the situation is the same: when a playback request is issued, the DVR sends the Entitlement Control Messages to the security module and, provided that the rights to watch the movie are entitled, the security module returns the key to decrypt the movie including the advertisements. The security module cannot lock the fast forward or jump function within the DVR.
In order to link the advertisement section with the valuable content, a solution was described in the document US2003/0154378. The broadcasted images contain two areas, an advertisement area and a valuable content area, the key to access the valuable area being watermarked in the advertisement area so that removing the advertisement area lead to forbidding the access to the valuable content.
In the document WO 2004/056116, the broadcast of advertisements on portable video device is duly accounted and charged to the advertiser. This document describe how collecting feedback information by watching the user's reaction such as modifying the sound level.